2020-12-23 1.调整mqtt挤下线，跑ui线程。2.LoadEvent_CheckLinkStatus方法调整

JLChen

2020-12-23 f9f9b0030fdd2691632569b7dcad9d0ddca5e4cf

 HDL_ON/UI/UI2/2-Classification/ClassificationPageBLL.cs

@@ -339,6 +339,7 @@
                var onoff = btn.IsSelected ? "on" : "off";
                var waitPage = new Loading();
                view.AddChidren(waitPage);
                waitPage.BackgroundColor = 0x00000000;
                waitPage.Start("");
                new System.Threading.Thread(() =>
                {
@@ -417,6 +418,7 @@
                btnOpen.IsSelected = true;
                btnClose.IsSelected = false;
                var waitPage = new Loading();
                waitPage.BackgroundColor = 0x00000000;
                view.AddChidren(waitPage);
                waitPage.Start("");
                new System.Threading.Thread(() =>